1. Field of Invention
This invention is a telescope type of guide relating to drilling, especially an accessory to hand-held drill for use in precisely placing cylindrical holes with direction stability, force and depth control.
2. Description Of Prior Art
Most of surgeons while preparing holes into or through bones by using hand-held drill would likely face common difficulties as other drill users which are difficult direction control, difficult depth control, poor force and stability control.
Because of those poor controls, it is not unusual to overprepare holes in depth and wrong direction which would cause unnecessary traumatic bone injury and lead to delayed healing or failure.
Heretofore a wide variety of guiding instruments have been developed and implemented for drilling control.
In the past. accessories as nose pieces have been used with drills to protect drill bit from damaging and help supporting stability in general drilling. Some nose pieces could also provide certain length adjustment. There was, however, no specific nose piece which could provide stability and direction control over uneven surface, specifically accurate drilling depth control and drilling force control while drilling through different hardness of working piece.
Another type of such instrument which is used in cerebral trephination by neurosurgeons comprised a sharp point guiding pin attached to the shaft of power drill and is used to prevent burr from passing beyond the skull. Surgeons regarded this instrument as unsatisfactory because poor depth control, lack of stability and force control which have forced surgeons using their fingers as additional guard to prevent plunging through the skull.
In orthopaedic surgery, surgeons use other type of instruments comprising a series of drilling sleeves and tap sleeves. Surgeons consider these instruments as unsatisfactory because of lengthy and complicated procedures poor depth and force control.
Most of dental implantologists use depth mark on the shaft of drill to control drilling depth. As far as direction, force and stability are controlled by free hand.
Most surgeons and drill users, therefore, would find it desirable to have an instrument or tool which could provide stability, force, direction and depth control at the same time while drilling with hand-held drill.